4 research outputs found
Challenges of beta-deformation
A brief review of problems, arising in the study of the beta-deformation,
also known as "refinement", which appears as a central difficult element in a
number of related modern subjects: beta \neq 1 is responsible for deviation
from free fermions in 2d conformal theories, from symmetric omega-backgrounds
with epsilon_2 = - epsilon_1 in instanton sums in 4d SYM theories, from
eigenvalue matrix models to beta-ensembles, from HOMFLY to super-polynomials in
Chern-Simons theory, from quantum groups to elliptic and hyperbolic algebras
etc. The main attention is paid to the context of AGT relation and its possible
generalizations.Comment: 20 page
One-loop derivation of the Wilson polygon - MHV amplitude duality
We discuss the origin of the Wilson polygon - MHV amplitude duality at the
perturbative level. It is shown that the duality for the MHV amplitudes at
one-loop level can be proven upon the peculiar change of variables in Feynman
parametrization and the use of the relation between Feynman integrals at the
different space-time dimensions. Some generalization of the duality which
implies the insertion of the particular vertex operator at the Wilson triangle
is found for the 3-point function. We discuss analytical structure of Wilson
loop diagrams and present the corresponding Landau equations. The geometrical
interpretation of the loop diagram in terms of the hyperbolic geometry is
discussed.Comment: 29 page